Although research has shown that sleep disorders are prevalent among people with dementia, the temporal relationship is unclear. We investigated whether atypical sleep characteristics were associated ...with incident dementia while accounting for baseline cognitive functioning.
Screening Across the Lifespan Twin (SALT) study participants were 11,247 individuals from the Swedish Twin Registry who were at least 65 years at baseline (1998-2002). Sleep and baseline cognitive functioning were assessed via the SALT telephone screening interview. Data on dementia diagnoses came from national health registers. Cox regression was performed to estimate hazard ratios for dementia.
After 17 years of follow-up, 1,850 dementia cases were identified. Short (≤6 hours) and extended (>9 hours) time in bed (TIB) compared to the middle reference group (hazard ratio = 1.40, 95% confidence interval = 1.06-1.85; hazard ratio = 1.11, 95% confidence interval = 1.00-1.24, respectively) and rising at 8:00 AM or later compared to earlier rising (hazard ratio = 1.12, 95% confidence interval = 1.01-1.24) were associated with higher dementia incidence. Bedtime, sleep quality, restorative sleep, and heavy snoring were not significant predictors. Findings stratified by baseline cognitive status indicated that the association between short TIB and dementia remained in those cognitively intact at the start.
Short and extended TIB and delayed rising among older adults predicted increased dementia incidence in the following 17 years. The pattern of findings suggests that extended TIB and late rising represent prodromal features whereas short TIB appeared to be a risk factor for dementia.
Body mass index (BMI) is associated with cognitive abilities, but the nature of the relationship remains largely unexplored. We aimed to investigate the bidirectional relationship from midlife ...through late-life, while considering sex differences and genetic predisposition to higher BMI. We used data from 23,892 individuals of European ancestry from the Health and Retirement Study, with longitudinal data on BMI and three established cognitive indices: mental status, episodic memory, and their sum, called total cognition. To investigate the dynamic relationship between BMI and cognitive abilities, we applied dual change score models of change from age 50 through 89, with a breakpoint at age 65 or 70. Models were further stratified by sex and genetic predisposition to higher BMI using tertiles of a polygenic score for BMI (PGS
). We demonstrated bidirectional effects between BMI and all three cognitive indices, with higher BMI contributing to steeper decline in cognitive abilities in both midlife and late-life, and higher cognitive abilities contributing to less decline in BMI in late-life. The effects of BMI on change in cognitive abilities were more evident in men compared to women, and among those in the lowest tertile of the PGS
compared to those in the highest tertile, while the effects of cognition on BMI were similar across groups. In conclusion, these findings highlight a reciprocal relationship between BMI and cognitive abilities, indicating that the negative effects of a higher BMI persist from midlife through late-life, and that weight-loss in late-life may be driven by cognitive decline.
Both physical functioning and cognitive abilities are important for well-being, not least in old age. Grip strength is often considered an indicator of general vitality and, as such, may predict ...cognitive functioning. Few longitudinal studies have examined the relationship between grip strength and cognition, especially where specific cognitive abilities have been targeted.
Participants (n = 708, age range: 40-86 years at baseline) came from the population-based longitudinal Swedish Adoption/Twin Study of Aging. We used a longitudinal follow-up of 6 waves during 20 years. For the analyses, we used latent growth modeling, where latent growth trajectories were fitted to the cognitive traits (verbal ability, spatial ability, processing speed, and memory) or to the grip strength values and each, respectively, treated as time-varying covariates of the other trait.
Results supported a longitudinal influence of grip strength on changes in cognitive function. Grip strength performance was associated with change in the 4 cognitive abilities after age 65 years.
A rather stable connection was found between grip strength and cognitive abilities starting around 65 years of age. The starting period suggests that the association may be due to lifestyle changes, such as retirement, or to acceleration of the aging processes.
Few studies have examined associations of multi-faceted demographic, health and lifestyle factors with long-term change in grip strength performance across the adult lifespan. The aim of this study ...was to examine the associations of risk factors in specific parts of the adult lifespan (e.g. in early midlife, in late midlife and in old adulthood) separately for women and men.
Data came from the longitudinal Swedish Adoption/Twin Study of Aging (SATSA). Grip strength performance was followed in 849 participants who were 50-88 years of age at baseline. The follow-up period with seven waves of data of grip strength was 22 years, and the risk factors were measured up to 20 years before the assessment of grip strength. Latent growth modelling was used for the longitudinal analyses.
A gender difference in the type of factors associated with grip strength performance and development across the adult lifespan was found. Significant factors for the age slopes for women were stress, smoking and dementia. For men, marital status, mean arterial pressure, physical activity at work and having a chronic disorder were of importance. These factors varied in their associations with grip strength across the adult lifespan.
Factors measured earlier in adulthood were associated with grip strength decline in late midlife and old adulthood. Gender-specific patterns of risk factors suggest that it may be worthwhile to conduct research on grip and muscle strength (and biological vitality) separately for men and women.
Higher body mass and obesity are associated with bodily pain, and rates of chronic pain increase among older adults. Most past studies are cross-sectional, precluding determination of the temporal ...relationship between body mass and pain. A longitudinal study of body mass and pain among middle-aged adults found that higher body mass index (BMI) led to greater lower back pain. No longitudinal study of BMI and pain has been conducted among adults older than 70 years. This study used dual change score models to determine the directional relationship between BMI and bodily pain in a sample of middle-aged and older adults. Participants (n = 1889) from the Swedish Twin Registry (baseline age range 40-93 years) completed at least 1 nurse assessment of BMI and self-report ratings of pain interference and joint pain. Pain interference was not associated with BMI, but joint pain was analyzed in univariate and bivariate models, with dual change score models modeling the relationship of BMI and joint pain across age, both independently and as part of bivariate relationships. The results indicated a reciprocal relationship between BMI and joint pain, but joint pain generally led to changes in BMI. In addition, the relationship changed with age, until approximately age 80 years, increasing joint pain contributed to higher BMI, but after that time increasing joint pain contributed to lower BMI. In addition, sex differences in the relationship between BMI and pain appeared after age 70 years. Thus, joint pain contributes to changes in BMI among middle-aged and older adults, but the relationship may change by age and sex.
In this report we analyzed genetically informative data to investigate within-person change and between-person differences in late-life cognitive abilities as a function of childhood social class. We ...used data from nine testing occasions spanning 28 y in the Swedish Adoption/Twin Study of Aging and parental social class based on the Swedish socioeconomic index. Cognitive ability included a general factor and the four domains of verbal, fluid, memory, and perceptual speed. Latent growth curve models of the longitudinal data tested whether level and change in cognitive performance differed as a function of childhood social class. Between–within twin-pair analyses were performed on twins reared apart to assess familial confounding. Childhood social class was significantly associated with mean-level cognitive performance at age 65 y, but not with rate of cognitive change. The association decreased in magnitude but remained significant after adjustments for level of education and the degree to which the rearing family was supportive toward education. A between-pair effect of childhood social class was significant in all cognitive domains, whereas within-pair estimates were attenuated, indicating genetic confounding. Thus, childhood social class is important for cognitive performance in adulthood on a population level, but the association is largely attributable to genetic influences.
Population-based health registers are potential assets in epidemiological research; however, the quality of case ascertainment is crucial.
To compare the case ascertainment of dementia, from the ...National Patient Register (NPR) and the Cause of Death Register (CDR) with dementia diagnoses from six Swedish population based studies.
Sensitivity, specificity, and positive predictive value (PPV) of dementia identification in NPR and CDR were estimated by individual record linkage with six Swedish population based studies (n = 19,035). Time to detection in NPR was estimated using data on dementia incidence from longitudinal studies with more than two decades of follow-up.
Barely half of the dementia cases were ever detected by NPR or CDR. Using data from longitudinal studies we estimated that a record with a dementia diagnosis appears in the NPR on average 5.5 years after first diagnosis. Although the ability of the registers to detect dementia cases was moderate, the ability to detect non-dementia cases was almost perfect (99%). When registers indicate that there is a dementia diagnosis, there are very few instances in which the clinicians determined the person was not demented. Indeed, PPVs were close to 90%. However, misclassification between dementia subtype diagnoses is quite common, especially in NPR.
Although the overall sensitivity is low, the specificity and the positive predictive value are very high. This suggests that hospital and death registers can be used to identify dementia cases in the community, but at the cost of missing a large proportion of the cases.
Shift work and cognitive aging: a longitudinal study Bokenberger, Kathleen; Ström, Peter; Dahl Aslan, Anna K ...
Scandinavian Journal of Work, Environment ＆ Health,
09/2017, Volume:
43, Issue:
5
Journal Article
Peer reviewed
Open access
Objectives: The few studies of shift work and late life cognitive functioning have yielded mixed findings. The aim of the present study is to estimate the association between shift-work experience ...and change in cognitive performance before and after retirement age among older adults who were gainfully employed. Methods: Five hundred and ninety five participants with no dementia were followed up for a mean of 17.6 standard deviation (SD) 8.8 years from a Swedish population-based sample. Participants had self-reported information on any type of shift-work experience (ever/never) in 1984 and measures of cognitive performance (verbal, spatial, memory, processing speed, and general cognitive ability) from up to 9 waves of cognitive assessments during 1986-2012. Night work history (ever/never) from 1998–2002 was available from a subsample (N=320). Early adult cognitive test scores were available for 77 men. Results: In latent growth curve modeling, there were no main effects of ＂any-type＂ or night shift work on the mean scores or rate of change in any of the cognitive domains. An interaction effect between any-type shift work and education on cognitive performance at retirement was noted. Lower-educated shift workers performed better on cognitive tests than lower-educated day workers at retirement. Sensitivity analyses, however, indicated that the interactions appeared to be driven by selection effects. Lower-educated day workers demonstrated poorer cognitive ability in early adulthood than lower-educated shift workers, who may have selected jobs entailing higher cognitive demand. Conclusion: There was no difference in late-life cognitive aging between individuals with a history of working shifts compared to those who had typical day work schedules during midlife.
Abstract
Background
The organizational principle of remaining at home has offset care from the hospital to the home of the older person where care from formal and informal caregivers is needed. ...Globally, formal care is often organized to handle singular and sporadic health problems, leading to the need for several health care providers. The need for an integrated care model was therefore recognized by health care authorities in one county in Sweden, who created a cross-organisational integrated care model to meet these challenges. The Mobile integrated care model with a home health care physician (MICM) is a collaboration between regional and municipal health care. Descriptions of patients’ and next of kin’s experiences of integrated care is however lacking, motivating exploration.
Method
A qualitative thematic study. Data collection was done before the patients met the MICM physician, and again six months later.
Results
The participants expected a sense of relief when admitted to MICM, and hoped for shared responsibility, building a personal contact and continuity but experienced lack of information about what MICM was. At the follow-up interview, participants described having an easier daily life. The increased access to the health care personnel (HCP) allowed participants to let go of responsibility, and created a sense of safety through the personalised contact and continuity. However, some felt ignored and that the personnel teamed up against the patient. The MICM structure was experienced as hierarchical, which influenced the possibility to participate. However, the home visits opened up the possibility for shared decision making.
Conclusion
Participants had an expectation of receiving safe and coherent health care, to share responsibility, personal contact and continuity. After six months, the participants expressed that MICM had provided an easier daily life. The direct access to HCP reduced their responsibility and they had created a personalised contact with the HCP and that the individual HCP mattered to them, which could be perceived as in line with the goals in the shift to local health care. The MICM was experienced as a hierarchic structure with impact on participation, indicating that all dimensions of person-centred care were not fulfilled.
Diabetes has been linked to dementia risk; however, the cognitive trajectories in older adults with diabetes remain unclear. We aimed to investigate the effect of prediabetes and diabetes on ...cognitive trajectories among cognitively intact older adults in a long-term follow-up study.
Within the Swedish Adoption/Twin Study of Aging, 793 cognitively intact older adults aged ≥50 were identified at baseline and followed for up to 23 years. Based on standardized scores from 11 cognitive tests, administered at baseline and up to seven follow-ups, four cognitive domains (verbal abilities, spatial/fluid, memory, perceptual speed) were identified by principal-component analysis. Prediabetes was defined according to blood glucose levels in diabetes-free participants. Diabetes was ascertained based on self-report, hypoglycemic medication use and blood glucose levels. Data were analyzed with linear mixed-effect models adjusting for potential confounders.
At baseline, 68 participants (8.6%) had prediabetes and 45 (5.7%) had diabetes. Compared to diabetes-free individuals, people with diabetes had a steeper decline over time in perceptual speed and verbal abilities. The annual declines in these domains were greater than the annual decline in memory. Prediabetes was associated with lower performance in memory in middle-age, but also associated with a less steep memory decline over the follow-up.
Diabetes is associated with a faster decline in perceptual speed and verbal abilities, while prediabetes is associated with lower memory performance in middle-age. However, the detrimental effects of hyperglycemia seem to not affect memory over time.
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